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Articles 1 - 30 of 141

Full-Text Articles in Environmental Sciences

Development Of A Meteorological Sensor Suite For Atmospheric Boundary Layer Measurement Using A Small Multirotor Unmanned Aerial System, Kevin A. Adkins Jun 2019

Development Of A Meteorological Sensor Suite For Atmospheric Boundary Layer Measurement Using A Small Multirotor Unmanned Aerial System, Kevin A. Adkins

Kevin A. Adkins, PhD

Small unmanned aerial systems (sUAS) are increasingly being used to conduct atmospheric research. Because of the dynamic nature and inhomogeneity of the atmospheric boundary layer (ABL), the ability of instrumented sUAS to make on-demand 3-dimensional high-resolution spatial measurements of atmospheric parameters makes them particularly suited to ABL investigations. Both fixed-wing and multirotor unmanned aircraft (UA) have been used for ABL investigations. Most investigations to date have included in-situ measurement of scalar quantities such as temperature, pressure and humidity. When wind has been measured, a variety of strategies have been used. Two of the most popular techniques have been deducing wind …


Modeling Spatial And Temporal Variation In Natural Background Specific Conductivity, John Olson, Susan M. Cormier Mar 2019

Modeling Spatial And Temporal Variation In Natural Background Specific Conductivity, John Olson, Susan M. Cormier

John Olson

ABSTRACT: Understanding how background levels of dissolved minerals vary in streams temporally and spatially is needed to assess salinization of fresh water, establish reasonable thresholds and restoration goals, and determine vulnerability to extreme climate events like drought. We developed a random forest model that predicts natural background specific conductivity (SC), a measure of total dissolved ions, for all stream segments in the contiguous United States at monthly time steps between the years 2001 to 2015. Models were trained using 11 796 observations made at 1785 minimally impaired stream segments and validated with observations from an additional 92 segments. Static predictors …


Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya Mar 2019

Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya

Umesh K. Haritashya

Meltwater runoff modeling from glacierized basins needs several input data, including total meltwater contributing area. This study utilizes optical remote sensing data to assess glacierized basins in the central Himalayas where snow and glaciers contribute substantially to the water resources. Result shows that there are four main water-bearing zones in the basin: (a) dry snow, (b) wet snow, (c) exposed glacial ice, and (d) debris-covered glacial ice, and it is possible to differentiate and map these zones and their spatio-temporal variations from satellite sensor data. These zones can then be incorporated in meltwater runoff modeling as separate entities because they …


Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson Dec 2018

Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson

John Olson

Agricultural, industrial and urban development have all contributed to increased salinity in streams and rivers, but the likely effects of future development and climate change are unknown. I developed two empirical models
to estimate how these combined effects might affect salinity by the end of this century (measured as electrical conductivity, EC). The first model predicts natural background from static (e.g. geology and soils) and dynamic
(i.e. climate and vegetation) environmental factors and explained 78% of the variation in EC. I then compared the estimated background EC with current measurements at 2001 sites chosen probabilistically from all conterminous USA streams. …


Edible Forest Gardens- Perennial Ag Fo Eco Regeneration .Pdf, Lisa Depiano Sep 2018

Edible Forest Gardens- Perennial Ag Fo Eco Regeneration .Pdf, Lisa Depiano

Lisa DePiano

A semester long course in Edible Forest Gardening and Perennial Agriculture


Tiered Approaches In Analyzing Rice Field Pesticide Fate And Transport For Ecological Risk Assessment, Ruoyu Wang Jul 2018

Tiered Approaches In Analyzing Rice Field Pesticide Fate And Transport For Ecological Risk Assessment, Ruoyu Wang

Ruoyu Wang

No abstract provided.


The Soil Moisture Velocity Equation, Fred L. Ogden, Craig C. Douglas Jun 2017

The Soil Moisture Velocity Equation, Fred L. Ogden, Craig C. Douglas

Fred L. Ogden

Numerical solution of the one-dimensional Richards’ equation is the recommended method for coupling groundwater to the atmosphere through the vadose zone in hyper-resolution Earth system models, but requires fine spatial discretization, is computationally expensive, and may not converge due to mathematical degeneracy or when sharp wetting fronts occur. We transformed the one-dimensional Richards’ equation into a new equation that describes the velocity of moisture content values in an unsaturated soil under the actions of capillarity and gravity. We call this new equation the Soil Moisture Velocity Equation (SMVE). The SMVE consists of two terms: an advection-like term that accounts for …


How Changing Climate Created Mount Desert Island, Catherine Schmitt Mar 2017

How Changing Climate Created Mount Desert Island, Catherine Schmitt

Catherine Schmitt

Acadia is a national park, the first place in eastern U.S. to receive such designation, because of its scenery. Diverse and exposed geology forms the foundation for Acadia’s beauty, but the landscape of today is the result of climate changes over millennia. Climate influences include a land surface worked by glaciers, and diverse flora and fauna as a result of the island’s position on the coast, within a transition zone between temperate ecosystems to the south and the boreal north.


Assessment Of Optional Sediment Transport Functions Via The Complex Watershed Simulation Model Swat, Ruoyu Wang Jan 2017

Assessment Of Optional Sediment Transport Functions Via The Complex Watershed Simulation Model Swat, Ruoyu Wang

Ruoyu Wang

The Soil andWater Assessment Tool 2012 (SWAT2012) offers four sediment routing methods
as optional alternatives to the default simplified Bagnold method. Previous studies compared only
one of these alternative sediment routing methods with the default method. The proposed study
evaluated the impacts of all four alternative sediment transport methods on sediment predictions:
the modified Bagnold equation, the Kodoatie equation, the Molinas and Wu equation, and the
Yang equation. The Arroyo Colorado Watershed, Texas, USA, was first calibrated for daily flow.
The sediment parameters were then calibrated to monthly sediment loads, using each of the four
sediment routing equations. An automatic …


Assessing The Potential To Decrease The Gulf Of Mexico Hypoxic Zone With Midwest Us Perennial Cellulosic Feedstock Production, Andy Vanloocke, Tracy E. Twine, Christopher J. Kucharik, Carl J. Bernacchi Jan 2017

Assessing The Potential To Decrease The Gulf Of Mexico Hypoxic Zone With Midwest Us Perennial Cellulosic Feedstock Production, Andy Vanloocke, Tracy E. Twine, Christopher J. Kucharik, Carl J. Bernacchi

Andy VanLoocke

The goal of this research was to determine the changes in streamflow, dissolved inorganic nitrogen (DIN) leaching and export to the Gulf of Mexico associated with a range of large-scale dedicated perennial cellulosic bioenergy production scenarios within in the Mississippi–Atchafalaya River Basin (MARB). To achieve this goal, we used Agro-IBIS, a vegetation model capable of simulating the biogeochemistry of row crops, miscanthus and switchgrass, coupled with THMB, a hydrology model capable of simulating streamflow and DIN export. Simulations were conducted at varying fertilizer application rates (0–200 kg N ha -1) and fractional replacement (5–25%) of current row crops with miscanthus …


Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, Jesse N. Miller, Andy Vanloocke, Nuria Gomez-Casanovas, Carl J. Bernacchi Jan 2017

Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, Jesse N. Miller, Andy Vanloocke, Nuria Gomez-Casanovas, Carl J. Bernacchi

Andy VanLoocke

The production of perennial cellulosic feedstocks for bioenergy presents the potential to diversify regional economies and the national energy supply, while also serving as climate ‘regulators’ due to a number of biogeochemical and biogeophysical differences relative to row crops. Numerous observational and model-based approaches have investigated biogeochemical trade-offs, such as increased carbon sequestration and increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biogeophysical changes associated with the difference in albedo (a), which could alter the local energy balance and cause local to regional cooling several times larger than that associated with offsetting carbon. Here, …


Combined And Synergistic Effects Of Climate Change And Urbanization On Water Quality In The Wolf Bay Watershed, Southern Alabama, Ruoyu Wang Jan 2017

Combined And Synergistic Effects Of Climate Change And Urbanization On Water Quality In The Wolf Bay Watershed, Southern Alabama, Ruoyu Wang

Ruoyu Wang

This study investigated potential changes in flow, total suspended solid (TSS) and nutrient (nitrogen and phosphorous) loadings under future climate change, land use/cover (LULC) change and combined change scenarios in the Wolf Bay watershed, southern Alabama, USA. Four Global Circulation Models (GCMs) under three Special Report Emission Scenarios (SRES) of greenhouse gas were used to assess the future climate change (2016–2040). Three projected LULC maps (2030) were employed to reflect different extents of urbanization in future. The individual, combined and synergistic impacts of LULC and climate change on water quantity/quality were analyzed by the Soil and Water Assessment Tool (SWAT). …


Biophysical And Hydrological Effects Of Future Climate Change Including Trends In Co2, In The St. Joseph River Watershed, Eastern Corn Belt, Ruoyu Wang Sep 2016

Biophysical And Hydrological Effects Of Future Climate Change Including Trends In Co2, In The St. Joseph River Watershed, Eastern Corn Belt, Ruoyu Wang

Ruoyu Wang

Future climate change has the potential to significantly impact crop growth, both directly due to CO2 enhancement and indirectly, through temperature and moisture impacts. This work investigates the biophysical and hydrological effects of future climate change, including trends in CO2, in the St. Joseph River watershed, Eastern Corn Belt. In this study, the Soil and Water Assessment Tool (SWAT) was first modified to take dynamic CO2 concentration as input. A regional crop leaf development curve from Landsat TM imagery was also used to adjust model performance in corn leaf area development for the historical period. A multi-objective calibration strategy was …


Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker Sep 2016

Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker

Xiaoyang Zhang

The exchange of carbon dioxide is a key measure of ecosystem metabolism and a critical intersection between the terrestrial biosphere and the Earth’s climate. Despite the general agreement that the terrestrial ecosystems in North America provide a sizeable carbon sink, the size and distribution of the sink remain uncertain. We use a data-driven approach to upscale eddy covariance flux observations from towers to the continental scale by integrating flux observations, meteorology, stand age,aboveground biomass, and a proxy for canopy nitrogen concentrations from AmeriFlux and Fluxnet-Canada Research Network as well as a variety of satellite data streams from the MODIS sensors. …


Water, Growth And The Endangered Species Act, Holly Doremus Aug 2016

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.


Water, Growth And The Endangered Species Act, Holly Doremus Aug 2016

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.


Water, Growth And The Endangered Species Act, Holly Doremus Aug 2016

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.


Determining The Influence Of Emission Pathways On Outgoing Longwave Radiation Over Africa, Thomas Rechtman Aug 2016

Determining The Influence Of Emission Pathways On Outgoing Longwave Radiation Over Africa, Thomas Rechtman

Thomas Rechtman

The increase in greenhouse gas (GHG) emissions into the atmosphere has long been know for it effects on the climate. As of yet, the amount of longwave radiation leaving the top of the atmosphere - known as outgoing longwave radiation or OLR - has not been studied in the context of cli- mate change on a regional basis. Using the Coupled Model Intercomparison Project (CMIP5) historical models and Representative Concentration Path- way (RCP) scenarios; along with the National Oceanic and Atmospheric Ad- ministrations (NOAA) OLR satellite data, we determine if observed trends in OLR are forced by GHG emissions or …


Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou Apr 2016

Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou

Shuang-ye Wu

In the Asian monsoon region, variations in the stable isotopic composition of speleothems have often been attributed to the "amount effect". However, an increasing number of studies suggest that the "amount effect" in local precipitation is insignificant or even non-existent. To explore this issue further, we examined the variability of daily stable isotopic composition (δ18O) in precipitation from September 2011 to November 2014 in Nanjing, eastern China. We found that intra-seasonal variations of δ18O during summer were not significantly correlated with local rainfall amount but could be linked to changes in the moisture source location and rainout processes in the …


Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu Apr 2016

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Shuang-ye Wu

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …


Transition From Contraction To Extension In The Northeastern Basin And Range: New Evidence From The Copper Mountains, Nevada, Jeffrey M. Rahl, Allen J. Mcgrew, Kenneth A. Foland Apr 2016

Transition From Contraction To Extension In The Northeastern Basin And Range: New Evidence From The Copper Mountains, Nevada, Jeffrey M. Rahl, Allen J. Mcgrew, Kenneth A. Foland

Allen J. McGrew

New mapping, structural analysis, and 40Ar/39Ar dating reveal an unusually well‐constrained history of Late Eocene extension in the Copper Mountains of the northern Basin and Range province. In this area, the northeast‐trending Copper Creek normal fault juxtaposes a distinctive sequence of metacarbonate and granitoid rocks against a footwall of Upper Precambrian to Lower Cambrian quartzite and phyllite. Correlation of the hanging wall with footwall rocks to the northwest provides an approximate piercing point that requires 8–12 km displacement in an ESE direction. This displaced fault slice is itself bounded above by another normal fault (the Meadow Fork Fault), which brings …


Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar Mar 2016

Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar

Umesh K. Haritashya

Meteorological data collected near the snout of the Gangotri Glacier suggest that the study area receives less rainfall. The average seasonal rainfall is observed to be about 260 mm. The rainfall distribution does not show any monsoon impact. Amount of seasonal rainfall is highly variable (131.4-368.8 mm) from year to year, but, in general, August had the maximum rainfall. A verage daily maximum and minimum temperatures were 14.7 and 4.1°C respectively, whereas average mean temperature was 9.4°C. July was recorded as the warmest month. During daytime, wind speed was four times higher than that at night-time. The average daytime and …


Multispectral Image Analysis Of Glaciers And Glacier Lakes In The Chugach Mountains, Alaska, Jeffrey Kargel, Matthew Beedle, Andrew Bush, Francisco Carreño, Elena Castellanos, Umesh Haritashya, Gregory Leonard, Javier Lillo, Ivan Lopez, Mark Pleasants, Edward Pollock, David Wolfe Mar 2016

Multispectral Image Analysis Of Glaciers And Glacier Lakes In The Chugach Mountains, Alaska, Jeffrey Kargel, Matthew Beedle, Andrew Bush, Francisco Carreño, Elena Castellanos, Umesh Haritashya, Gregory Leonard, Javier Lillo, Ivan Lopez, Mark Pleasants, Edward Pollock, David Wolfe

Umesh Haritashya

The Chugach Mountains contain the largest nonpolar alpine glaciers in the world and include a wide variety of glacier types: some are land terminating; some calve variously into tidewater, lakes, and rivers; some are heavily debris covered; some are surge-type, whereas others are neither debris covered nor surge type. Nearly all are retreating, thinning, or both, though some rare ones are advancing, and some are thickening at high elevations. To assist the further documentation of changes, we establish an inventory of glaciers in the eastern Chugach Mountains. Several case studies of diverse glacier types showcase remotesensing applications and are used …


Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya Mar 2016

Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya

Umesh K. Haritashya

The objective of this encyclopedia is to present the current state of scientific understanding of various aspects of earth’s cryosphere – snow, glaciers, ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and permafrost – and their related interdisciplinary connections under one umbrella. Therefore, every effort has been made to provide a comprehensive coverage of cryosphere by including a broad array of topics, such as the atmospheric processes responsible for snow formation; snowfall observations; snow cover and snow surveys; transformation of snow to ice and changes in their properties; classification of ice and glaciers and their worldwide …


Iceland: Extreme Learning In The Land Of Fire And Ice, Jason Polk, Leslie North Feb 2016

Iceland: Extreme Learning In The Land Of Fire And Ice, Jason Polk, Leslie North

Leslie North

WKU Libraries kicked off the spring season of "Far Away Places" with Dr. Jason Polk and Dr. Leslie North, Asstant Professors from the Department of Geography and Geology at WKU, who talked about leading a study abroad group to Iceland in the summer of 2015. WKU Libraries kicks off the spring season of Far Away Places with Jason Polk and Leslie North, Asst. Professors from the Department of Geography and Geology at WKU, who will be talking about leading a study abroad group to Iceland in the summer of 2015. Dr. Polk and Dr. North co-taught this course with faculty …


Logistic Curves, Extraction Costs And Peak Oil, Robert Brecha Jan 2016

Logistic Curves, Extraction Costs And Peak Oil, Robert Brecha

Robert J. Brecha

Debates about the possibility of a near-term maximum in world oil production have become increasingly prominent over the past decade, with the focus often being on the quantification of geologically available and technologically recoverable amounts of oil in the ground. Economically, the important parameter is not a physical limit to resources in the ground, but whether market price signals and costs of extraction will indicate the efficiency of extracting conventional or nonconventional resources as opposed to making substitutions over time for other fuels and technologies. We present a hybrid approach to the peak-oil question with two models in which the …


Role Of Multiple High-Capacity Irrigation Wells On A Surficial Sand And Gravel Aquifer, Logan Seipel, Eric Wade Peterson, David H. Malone, Jason F. Thomason Dec 2015

Role Of Multiple High-Capacity Irrigation Wells On A Surficial Sand And Gravel Aquifer, Logan Seipel, Eric Wade Peterson, David H. Malone, Jason F. Thomason

Eric Wade Peterson

Within McHenry County, IL, the fastest growing county in Illinois, groundwater is used for 100% of
the water needs. Concerns over water resources have prompted the investigation of the surficial
sand and gravel aquifers of the county. While the eastern portion of the county is urbanizing, the
western portion remains devoted to agriculture. High-capacity irrigation wells screened within
the surficial sand and gravel aquifer are used for crop production. To assess the impacts of the ir-
rigation wells on the aquifer, a groundwater flow model was developed to examine five different
scenarios reflecting drought conditions and increased pumping. Results show …


Simulating Management Effects On Crop Production, Tile Drainage, And Water Quality Using Rzwqm–Dssat, S. A. Saseendran, Liwang Ma, Robert W. Malone, Philip Heilman, Lajpat R. Ahuja, Ramesh S. Kanwar, Douglas L. Karlen, G. Hoogenboom Dec 2015

Simulating Management Effects On Crop Production, Tile Drainage, And Water Quality Using Rzwqm–Dssat, S. A. Saseendran, Liwang Ma, Robert W. Malone, Philip Heilman, Lajpat R. Ahuja, Ramesh S. Kanwar, Douglas L. Karlen, G. Hoogenboom

Douglas L Karlen

The objective of this study was to explore if more crop-specific plant growth modules can improve simulations of crop yields, and N in tile flow under different management practices compared with a generic plant growth module. We calibrated and evaluated the Root Zone Water Quality Model (RZWQM) with the Decision Support for Agrotechnology Transfer (DSSAT v3.5) plant growth modules (RZWQM–DSSAT) for simulating tillage (NT — no till, RT — ridge till, CP — chisel plow, and MP — moldboard plow), crop rotation {CC — continuous corn, and CS — corn (Zea mays L.)–soybean [Glycine max (L.) Merr.]}, and nitrogen (N) …


Evaluating And Predicting Agricultural Management Effects Under Tile Drainage Using Modified Apsim, Robert W. Malone, N. Huth, P. S. Carberry, Liwang Ma, Thomas C. Kaspar, Douglas L. Karlen, T. Meade, Ramesh S. Kanwar, Philip Heilman Dec 2015

Evaluating And Predicting Agricultural Management Effects Under Tile Drainage Using Modified Apsim, Robert W. Malone, N. Huth, P. S. Carberry, Liwang Ma, Thomas C. Kaspar, Douglas L. Karlen, T. Meade, Ramesh S. Kanwar, Philip Heilman

Douglas L Karlen

An accurate and management sensitive simulation model for tile-drained Midwestern soils is needed to optimize the use of agricultural management practices (e.g., winter cover crops) to reduce nitrate leaching without adversely affecting corn yield. Our objectives were to enhance the Agricultural Production Systems Simulator (APSIM) for tile drainage, test the modified model for several management scenarios, and then predict nitrate leaching with and without winter wheat cover crop. Twelve years of data (1990–2001) from northeast Iowa were used for model testing. Management scenarios included continuous corn and corn–soybean rotations with single or split N applications. For 38 of 44 observations, …


Effects Of Liquid Swine Manure Applications On No3–N Leaching Losses To Subsurface Drainage Water From Loamy Soils In Iowa, Allah Bakhsh, Ramesh S. Kanwar, Douglas Karlen Dec 2015

Effects Of Liquid Swine Manure Applications On No3–N Leaching Losses To Subsurface Drainage Water From Loamy Soils In Iowa, Allah Bakhsh, Ramesh S. Kanwar, Douglas Karlen

Douglas L Karlen

Long-term applications of organic or inorganic sources of N to croplands can increase the leaching potential of nitrate–nitrogen (NO3–N) for soils underlain by subsurface drainage “tile” network. A field study was conducted for 6 years (1993–1998) to determine the effects of liquid swine manure and urea ammonium nitrate (UAN) solution fertilizer applications on NO3–N concentrations and NO3–N losses with subsurface drainage water under continuous corn (Zea maize L.) and corn after soybean (Glycine max. L.) production systems. The field data collected at Iowa State University's northeastern research center near Nashua, Iowa, under …